A mining academic says coal mining can co-exist with the production of irrigated crops on a rotational basis.

Subsidence from underground mines can affect the level of the ground, altering surface water flows and affecting farmers' crops, which rely on the even spread of irrigation water.

Farmers say there's no way the industries can co-exist, but the Head of the School of Mining and Engineering at the University of NSW thinks it is possible.

Professor Bruce Hebblewhite says subsidence can be predicted and that means that farmers can plan their cropping schedule accordingly.

"What I'm suggesting is that mining might take place in a particular longwall panel one year where there are fields that are not used for cotton production. (After the mining is finished), the land could be re-levelled and you'd be back to a suitable location for ongoing production."

Professor Hebblewhite says it's unclear who would pick up the tab for the rehabilitation work, but it is possible that mining companies would foot the bill.

"It depends on the location, which state they're in, what arrangements are in place. There is certainly evidence that the industry works collaboratively with land users under different arrangements, so it's possible."